When I saw the beach itself, I remembered learning/trying to waterski behind Larson's power boat. And Dad and Jack Larson getting invited for drinks by this woman who lived up the shore. Mom said Mrs. Larson was upset that just they were invited, and insisted on some kids going along. I went, but all I remember was a big picture window with a great view.
At the ferry dock to Rock Island, a reminder not to put fish waste in the trash right next to a snack wagon: